(a) Field of the Invention
The present invention relates to radio frequency technology and more particularly to a radio frequency management system for use in a shop inventory control system.
(b) Description of the Prior Art
Many different types of radio frequency identification devices are known. In a typical application of radio frequency identification, each product to be identified carries a chip that has identification data stored in a read only memory or read write memory therein, and a reading apparatus is operated to transmit a radio frequency signal to the chip via an antenna so that the storage data of the chip is fetched and sent back to the antenna by means of a radio carrier. The fetched data is then demodulated for further data processing. This technology can be applied to product distribution management to save much management time and labor. It has become increasingly popular for radio frequency management to be applied in different industries.
Currently, radio frequency identification applications are limited to short distance induction, i.e., for wireless data transmission at a distance within 10˜30 cm from the products. Beyond this range, the effect becomes poor because of interference of similar surrounding frequencies. Further, when multiple reading devices are arranged in parallel, the antenna transmission may cause erroneous readings of the data outside the desired range, thereby causing trouble and affecting the management integrity. Therefore, the reading operation is usually performed in a particular place, and sometimes only a mobile reading operation can be performed.
Therefore, it is desirable to provide a radio frequency identification management device that eliminates the problem of reading errors present in prior art designs.